In recent years, the television broadcast has spread in the form of not only surface-wave broadcast, but also satellite broadcast using artificial satellites. Consequently, the number of channels is increasing. Increasing the number of channels inevitably increases the number of television programs. There is a trend of providing television programs that more properly suite the audience interests.
It is beneficial for the audience to be able to watch and listen to television programs that suit their interests. However, it has been difficult and troublesome to search for the intended television programs out of a large number of television programs and out of information about them.
Information about television programs is provided in the forms of television program guides distributed on paper media such as newspapers and EPG (Electronic Program Guide) distributed via networks. These guides are available in table formats comprising broadcast stations associated with broadcast times. Though the tabular television program guides are well designed for high visibility, the amount of information is large. The audience feels it difficult to search for intended television programs and needs a long time for the search.
There is proposed the method of using keywords to be able to easily search for television programs intended by the audience. According to this method, for example, the audience selects one or more of a plurality of predetermined keywords that match the audience's interest. Television program information including the selected keyword is extracted from the EPG and is provided to the audience.
However, the EPG is not necessarily configured to include only the information that accurately represents the television program contents. The use of inappropriate keywords may fail to retrieve appropriate television programs using keywords. Selection of keywords may or may not succeed in retrieving eligible television programs. For example, using the word “America” as a keyword fails to extract television programs containing the word (information) “USA” though these programs concern America.